Arsenic removal from contaminated water by iron oxide sorbents and porous ceramic membranes

An adsorption-filtration process using porous ceramic membranes is proposed for the purification of water from arsenic As(V) ions. Iron oxide in nanoparticle and microparticle form is used as adsorbent in combination with ultrafiltration and microfiltration asymmetric multilayer ceramic membranes, respectively. As appeared from the results in the adsorption-ultrafiltration process, 2 g l(-1) nanoparticle adsorbent lowers the arsenate concentration from an initial concentration of 1 mg l(-1) down to 10 mu g l(-1). The subsequent ultrafiltration process shows complete nanoparticle rejection producing therefore purified water with arsenic content lower than 10 mu g l(-1) at a flux of 156 kg h(-1) m(-2) under a moderate pressure difference of 3 x 10(5) Nt m(-2).